Corrosion inhibiting sprayable thermoplastic cover for mechanical assemblies, and methods of making and using

ABSTRACT

A Corrosion Inhibiting Sprayable Thermoplastic (“CIST”) cover is formed by spraying melted CIST onto a mold, allowing the CIST to cure, removing the cured cover from the mold using a series of cuts if necessary, positioning the cover on a mechanical assembly whose shape is significantly identical to the mold, and fusing the cuts on the cover using heat to reform the cover on the mechanical assembly.

BACKGROUND OF THE INVENTION

The present invention relates to protective covers for mechanical assemblies, and more specifically, to a thermoplastic cover for bearing assemblies, and the method of making this cover.

Industrial operations such as manufacturing lines often come to a screeching halt when mechanisms in the infrastructure malfunction or stop working. These failures are costly, potentially dangerous, and frustrating. Mechanical problems in an industrial operation are particularly troublesome insofar as it isn't usually possible to “swap out” a bad part, so repairs often require shutting down the entire operation.

Corrosion and contamination are leading causes of premature failure in rotating systems such as bearing assemblies. In an effort to prevent these issues, Corrosion Inhibiting Sprayable Thermoplastics (“CISTs”) are used in the industry to protect both stored and operational bearing assemblies.

The conventional delivery method for CISTs is mobilizing spraying equipment and applying the thermoplastic product directly onto the bearing assembly as a hot liquid. Said another way, the spraying equipment is brought to the bearing assembly, and the CIST is applied in situ. This is considered the best procedure because it isn't practical to remove bearing assemblies from industrial operations, treat them, and return them to the underlying structure.

Once the liquefied thermoplastic is cool, it becomes a flexible solid covering over the bearing, creating a barrier to corrosion and contamination entry. The thermoplastic does not bond to the bearing housing or shaft surface, thereby allowing both to function freely underneath the coating. This method is very effective, and the life of protected equipment is increased exponentially. Unfortunately, however, this system has shortcomings.

One problem of applying CIST via mobilized spraying is that installed bearing assemblies are often difficult to access with the application equipment due to length of spray hose, size of application equipment, and/or limited access to surfaces with the spray gun. Another issue is the cost of application equipment. Yet another shortcoming is the significant time that is necessary for application equipment to melt the thermoplastic, which adds to equipment downtime.

As can be seen, there is a need for a protective thermoplastic cover for bearing assemblies that doesn't require mobilized spraying equipment in situ. It is desirable that this cover can be fit onto bearing assemblies that are hard to access. It is also desirable that this cover is relatively inexpensive, easy to use, and easy to transport. It is also desirable that the cover can be fixed relatively quickly, and with standard tools and equipment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a photograph of a bearing assembly needing protection;

FIGS. 2-4 are photographs of a CIST cover that has been removed from a mold, shown in different views;

FIG. 5 is a photograph of a cover partially installed on a bearing assembly;

FIGS. 6-7 are photographs of a cover that has been installed on a bearing assembly, shown in different views;

FIG. 8 is a photograph of a cover being sealed back together on a bearing assembly; and

FIG. 9 is the finished cover.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description is of the best currently contemplated modes of carrying out exemplary embodiments of the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims.

The following structure numbers shall apply to the following structures among the various FIGS.:

-   10-Cover; -   12-Mold; -   14-Cut; -   15-Partial section; -   17-Mechanical tie; -   20-Bearing assembly; and -   22-Heat source.

Broadly, the present invention is a thermoplastic cover that is formed on a mold, removed from the mold using a series of cuts, positioned on a mechanical part whose shape is significantly identical to the mold, and reformed as a cover by fusing the cuts using heat.

Referring to the figures, FIG. 1 depicts bearing assembly 20 that would benefit from receiving a cover. It should be understood that other mechanisms with moving parts are within the scope of the invention, and that bearing assemblies are used as an example.

Cover 10 of the present invention is formed by creating a mold, applying CIST through spray application or injection molding, allow thermoplastic to cool, and removing thermoplastic cover from mold by cutting. The preferred CIST is Enviropeel E170 from Alocit & Enviropeel USA, of Indianapolis, Ind., although other similar thermoplastics, especially having characteristics of a melting and hardening point of 130° C. to 180° C., and the ability to melt and harden multiple times, could also be employed.

FIGS. 2-4 depict cover 10 that has been removed from mold and is ready for installation onto bearing assembly 20. FIG. 5 depicts partial section 15 fitted onto bearing assembly, FIG. 6 depicts entire cut cover in position on bearing assembly, and FIG. 7 depicts cut cover retained in position with mechanical tie 17.

As shown in FIG. 8, cuts 14 are sealed back together using heat source 22, then allowed to cool completely. The finished cover 10 is shown in FIG. 9. The mechanical assembly is now ready to use.

Specifications of certain structures and components of the present invention have been established in the process of developing and perfecting prototypes and working models. These specifications are set forth for purposes of describing an embodiment, and setting forth the best mode, but should not be construed as teaching the only possible embodiment. Ranges of values set forth inherently include those values, as well as all increments between. Also, it should be understood that all values are “approximately”, and “approximately” and the like, unless otherwise stated or contrary to common sense, are +/−10%. 

What is claimed is:
 1. A molded CIST cover for a mechanical assembly including: A. A first partial section including a first end; B. A second partial section including an second end, said first partial section and said second partial section separated one from another by a shared lateral cut; and C. At least one longitudinal cut defined by one of said partial sections, wherein said CIST cover is sized and shaped to conform to said mechanical assembly.
 2. The molded CIST cover of claim 1 wherein said CIST has a melting and hardening point of approximately 130° C. to 180° C.
 3. The molded CIST cover of claim 2 wherein said CIST has ability to melt and harden multiple times.
 4. The molded CIST cover of claim 1 wherein said first end is a closed end.
 5. The molded CIST cover of claim 4 wherein said second end is an opened end.
 6. The molded CIST cover of claim 1 wherein said at least one longitudinal cut is defined by said second partial section.
 7. The molded CIST cover of claim 1 having a thickness of approximately 4 to 10 mm thick.
 8. A method of producing a CIST cover for a mechanical assembly including the steps of: A. Spraying a melted CIST onto a mold; B. Allowing said melted CIST to cure; C. Cutting said cured CIST to create at least two partial sections; and D. Removing said at least two partial sections from said mold.
 9. The method of claim 8 further including the step of longitudinally cutting at least one of two partial sections.
 10. The method of claim 8 further including the step of selecting a mold that is substantially similarly sized and shaped to said mechanical assembly.
 11. The method of claim 8 wherein said step of spraying a melted CIST onto a mold includes the step of employing a CIST having melting and hardening point of approximately 130° C. to 180° C.
 12. A method of protecting a mechanical assembly including the steps of: A. Positioning a first partial section of a CIST cover onto the corresponding first portion of a mechanical assembly; B. Positioning a second partial section of said CIST cover onto the corresponding second portion of a mechanical assembly; C. Applying a heat source to melt said first partial section to said second partial section; and D. Allowing said first partial section and said second partial section to cure.
 13. The method of claim 12 wherein said step of applying a heat source includes the step of applying a heat source having a temperature of approximately 100 to 200° C.
 14. The method of claim 12 further comprising the step of securing said first partial section onto said corresponding portion of said mechanical assembly using at least one mechanical tie prior to said step of applying said heat source.
 15. The method of claim 14 further comprising the step of removing said mechanical tie. 